Asked if the bullets found in Coulston’s bedroom matched the bullets found in Parkinson, Mr Stefanovic said: “Maybe.”

“They may be, but at the time they were first examined, the firearms examiner, was unsure. He stopped short of saying they match and said that it may require further examination under a scanning electron microscope,” Mr Stefanovic told Sunday Night.

But he believed it never happened.

Coulston is serving three life sentences for the Burwood Triple Murders. He is detained at HM Prison Barwon in Anakie, Victoria.